The Black Alder Alnus glutinosa are native trees and there are several along the river and canal banks in our Park. They can survive periodic flooding because they have a remarkable network of tiny air spaces in special tissues called aerenchyma and special green photosynthesising cells in their trunks that produce oxygen from water and carbon dioxide from their own respiration which is channeled into these air spaces. When trees are under water without this aerenchyma they cannot breathe.Soon some of these trees will be labelled to help you identify them, but look out for their distinctive catkins and cones and leaves.

Did you know ? Alder cones are used by those with aquaria to lower the pH of the water!!!!

Alder leaves with a very distinctive blunt end with a nick in the middle